question about oversize holes in brake drums

Hello,

I just bought a replacement rear brake drum for my '66. (original 9" brakes). When I got it I found that the holes for the lugs are much larger than the splined shank on the wheel studs. I called the supplier and he called the vendor (Rugged Ridge) and they said that that was normal and they would be fine and not to worry about it. However EVERY brake drum that I've seen has had the wheel stud PRESSED into both the hub and brake drum and I'm concerned that these are too loose and will allow the drum to move around and affect the braking AND will eventually lead to the holes being wallowed out. I measured everything and here's what I found: NEW studs .617" dia, Old studs .620", old drum .609", new drum .642". Both the old and the new studs move around freely in the hole in the new drum. Note that both studs were a press fit in the old drum. In fact, the old stud was 0.011" larger than the hole! It took a LARGE hydraulic press to get them out!

I know that some people have enlarged the hole in their brake drums so that they can get them off without having to remove the hub and having to use a press but I think that 0.025" clearance is way too much. Does anyone have any knowledge or experience with this???

 

Joe,
My guess is that is just a little too much clearance. Why are you spending money on 9" brakes anyway? Most Jeepers I know put 11" drum conversions or even disc conversions on their Jeeps.
Myself, I have done the 11" conversion from an original 9" and the difference is night and day. 9" brakes are just not adequate IMHO.

Don

 

Good point Howard. If the drums locate tight on that hub, that will take care of runout.
I still don't like 9" brakes though.

Don